PEOPLE Explains: All About Chappaquiddick, the Shocking Kennedy Scandal That Left One Woman Dead

Chappaquiddick is back in the national spotlight thanks to an upcoming movie (due out in April) and recently released trailer that is centered around the scandal that badly scarred the late senator Ted Kennedy’s political career.

While what actually occurred on that night remains a mystery, we’re taking a look back at the incident and the need-to-know facts before you see the movie.

On July 18, 1969, Ted’s black Oldsmobile crashed off a small bridge on the tiny Massachusetts island of Chappaquiddick and landed in the water. The next morning the body of Mary Jo Kopechne, a young woman who had worked for Ted’s late brother Robert F. Kennedy, was found inside the mostly-submerged car.

Ted and Kopechne had attended a party with friends earlier that night at a rented cottage on the island, a small stretch of land that is part of the better-known island of Martha’s Vineyard, a popular vacation destination for old-money families. Reportedly only 12 people were at the gathering – Ted, five other married men and six so-called “Boiler Room Girls,” the name given to a clutch of young unmarried female campaign strategists, including Kopechne, who had worked on Robert’s presidential campaign before he was assassinated in 1968.